Electron emission device



Filed Aug. 19, 1930 2 Sheets-Sheet l` Jne 18, 1935; T, w SUKUMLYN 2,005,330

ELECTRON EMISSION DEVICE Filed Aug. 19, 1950 2 Sheets-Sheet 2 A #crm ely 2 conical form, due to the mutual repulsion effect between the electrons. However, theconverging path 2d materially restricts the electrons against spreading out, and the result is that an electron stream of comparatively large concentration is obtained.

In order to adjust the degree of concentration of the stream 26, I provide electrical means for setting the relative potentials of the members 25, 26, and cathode I8. The potentials of either or both members 25, 26.v can be adjusted, as by the aid of a tap 1M on a battery 39, located in a circuit between the cathode I8 and the mem-. ber 25. Similarly, the potential of member 26 can be set by proper choice of potentialffor bat-l' tery 4I located in this circuitl), .andto the polsi-e tive side of which the member` 26 connects, 'as by a lead-in rod 42.

A similar lead-ini 43 is shown for member 26.

By this means,

(Withnflimits) of stream 28 can be..obtained. In orderfto 'obtain [a greater. control ofthe stream '26, any .desired series of coaxialdirecting anode members can be'used,.anyor all of which Vhas an adjustablepotential. :.Thus in Fig. 3, there are shown substantiallythesame type of tube as in Fig. `1, .except for the matters now to be detailed.k 'e l The `:directing `anode structure: in this formv includes two pairs of axially spaced truncated cones. One set, 29 and 39,v nearest the grid 21 is electrically .joined 4to the lead-in rod 3|. The

other set, 32 and 33 `dene a slightly wider annular space for stream 28 and forms a virtual extensionof the truncated cone .structure formed by-members 29, 38. The degree of convergence of members 32, 33 .can loe-different from-that ofmembers 29, 38. The inner member33 canbe joined electricallyto members 29,' 38, vas vby con'- nection .36,- so that rall three of` thesemembers are atthe same positive potential of battery III. The outer member 32 can be joined yto a lead-in rod 35 connectedto .a top v36 on battery .39. Y

The cathode or lament 31 is shown inthis instanceas formed oftwoturns. In order toV lead 01T any undesired positive ions (Jin kcaseta gas filled tube is used)fromv the neighborhood of cathode 31 and grid 21 an electrode 44 of plate form .can be :disposed below vthe `cathode and kept at a proper potential as by 'albatteryV It is to be noted vthat in both forms of- Figs. 1 and f3, Ythe grid electrode 21 and'cathode I8 or 31 have an eiective length' conforming with the annular base of the vstream 28.' `In .this

Way, n'o serious .concentration of ions can be vsecured on any spot on these electrodes, thus permitting ythe grid .to perform its function accurately.

being Ajoined yto It'is of course under- 53, 54 conforming with Vthe plurality vof ycon.- centric annular spaces vof the ,directing anode,

i ment of.. any degree of convergence members 41, 49 .l

of .course hasia plurality of spacesl as well as with the configuration of cathode 55.

Fig. 5 shows. a form of the device which is a combination of Figs. 3 and 4. Thus there are four sets of concentric members forming the directing anode structure. Two ofk these sets such as 56, 51, and 58, 59 are concentric; While the other two sets 60, 6I and 62, 63 form respectively axial extensions o f the sets 56, 51 and 58, 59. In this form, the inner members 59, 63, 51 6I, arev joined electrically together and to the outerfmembers-rli,l 58. A common lead-in 64 is provided for these six members.

The outer members 68 and 62 of the superimposedwextension are also joined together and to a'fcommon ,-leadfin 69. By proper adjustment of -the..relative potentials of these two 68, Y62 and of the others' forming the anode stru'cture, lthe desiredV adjustthe degree of convergence of beam 28 members directing can 4vbe obtained.

vIn both forms of Figsf and 5, 'the axially spaced sets denne annular spaces that are wider as the convergence proceeds. This is yusefulto ensure that any widened stream at the dischargeend oflthe bottom set beaccommodated.

It lisoffcourse possible to use the device in gas-lilled tubes for effecting a uorescent coatingon the end of the tube. Such a structure is'A shown diagrammaticaHyjinFig. 6,

stream 28; in this instance an electromagnetic control is indicated rby the aid of coils-68.

lemma v -LfAn velectron emission device, comprising a cathode, a directing anode providing `a converging path for theelectronstreamfrom the cath# ode, said ecting anode j said members and.V said cathode being adapted to havektherelative potential therebetween-adelectrode. f. f

4. An electron emission device, comprising-a' cathode foremitting electrons from Vawide-base,

.means forA lconverging the stream ;of,`.electrons as they kprogress from the having La conve directed toward one end for the cathode the converging means and the controlelectrode. Y i 'f i 5.7An electron emission device, comprising a cathode having an active length vfrom which a stream of electrons is emitted, the stream being of the tube, the base of the stream conforming to the active length of the cathode, a control electrode adjacent thel cathodeand having aform conforming therewith, a member upon which. the electrons are received another electrode back of the cathode for receiving ions proceeding in a direction opposite the desired Astreamrof electrons and an envelope for the electrodes.

6. `The combinationas set forth in claim 5, in which means are included for convergingthe stream of electrons. 1

7. The combination as setforth in claim 5, in which the control electrode rdeines an opening which is disposed opposite the convolutons of the cathode, said convolutions being disposed to define a passageway opposite the opening.`

8. An electrode structure for directing electrons in an electron emission device, comprising a plurality oi' sets of converging nested members,

ast two such members, said between them a converging bers, 'and the sets space, and the sets being axially spaced with respect to each other.

9. An electrode structure-for directing electrons in anelectron emission device, comprising a plurality of sets of converging nested members, each set having at least two such members, and the sets being other, the nested members forming annular passageways, the Width of the passageways of a succeeding set being greater thanV that of the preceding set. Y

10. An electrode structure for directing electronsin an electron emission device, comprising a plurality of sets of converging nested members, each set having ,at least two such membeing axially spaced with respect to each other, and means for electrically connecting the inner of the members together.

11. An electron emission device, comprising a cathode, and a directing anode, said anode being formed of a pair of annular metallic members 'defining an annulaci` converging path be- `'tween them for the Alectrons emitted from the cathode, each of said members being adapted to be maintained at a diierent potential value with respect to said cathode.

THOMAS W. SUKUMLYN.

axially spaced with respect toeach 

